diff --git a/graphql.gemspec b/graphql.gemspec
index abb03cd849..30bb67c69a 100644
--- a/graphql.gemspec
+++ b/graphql.gemspec
@@ -37,6 +37,7 @@ Gem::Specification.new do |s|
 
   s.add_development_dependency "minitest"
   s.add_development_dependency "minitest-focus"
+  s.add_development_dependency "minitest-mock"
   s.add_development_dependency "minitest-reporters"
   s.add_development_dependency "ostruct"
   s.add_development_dependency "rake"
diff --git a/lib/graphql/language.rb b/lib/graphql/language.rb
index b230d340ab..1f40cbb04d 100644
--- a/lib/graphql/language.rb
+++ b/lib/graphql/language.rb
@@ -77,7 +77,10 @@ def self.escape_single_quoted_newlines(query_str)
       new_query_str || query_str
     end
 
+    LEADING_REGEX = Regexp.union(" ", *Lexer::Punctuation.constants.map { |const| Lexer::Punctuation.const_get(const) })
+
     INVALID_NUMBER_FOLLOWED_BY_NAME_REGEXP = %r{
+      (?<leading>#{LEADING_REGEX})
       (
         ((?<num>#{Lexer::INT_REGEXP}(#{Lexer::FLOAT_EXP_REGEXP})?)(?<name>#{Lexer::IDENTIFIER_REGEXP})#{Lexer::IGNORE_REGEXP}:)
         |
@@ -88,7 +91,7 @@ def self.escape_single_quoted_newlines(query_str)
 
     def self.add_space_between_numbers_and_names(query_str)
       if query_str.match?(INVALID_NUMBER_FOLLOWED_BY_NAME_REGEXP)
-        query_str.gsub(INVALID_NUMBER_FOLLOWED_BY_NAME_REGEXP, "\\k<num> \\k<name>:")
+        query_str.gsub(INVALID_NUMBER_FOLLOWED_BY_NAME_REGEXP, "\\k<leading>\\k<num> \\k<name>:")
       else
         query_str
       end
diff --git a/spec/graphql/language/parser_spec.rb b/spec/graphql/language/parser_spec.rb
index 1308f0a5f8..9f5a366c15 100644
--- a/spec/graphql/language/parser_spec.rb
+++ b/spec/graphql/language/parser_spec.rb
@@ -267,6 +267,7 @@
       "{ a(b: 123e5 ) }" => nil,
       "{ a(b: 12.3e5) }" => nil,
       "{ a(b: 12.3e5 ) }" => nil,
+      "query($cursor1_something: Int) { f(a: $cursor1_something) }" => nil,
       "query($obj: Input = { a: 1e5b: 2c: 3e-1}) { t }" => "query($obj: Input = { a: 1e5 b: 2 c: 3e-1}) { t }" ,
     }
 
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index cd5dd98d88..0e402325bb 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -51,6 +51,7 @@
 require "minitest/autorun"
 require "minitest/focus"
 require "minitest/reporters"
+require "minitest/mock"
 require "graphql/batch"
 
 running_in_rubymine = ENV["RM_INFO"]